Sales and profits at AstraZeneca have tumbled in 2012 after patents expired on
some of the company’s best-selling medicines and sparked competition
from cheaper medicines.

Britain’s second biggest pharmaceutical company saw revenues fall 21pc to $6.7bn (£4.3bn) while profits tumbled 38pc to $1.76bn in the second quarter of the year, leaving half-year profits down by the same margin at $3.82bn pre-tax.

The decline had been expected by the company because of the end of patent protection on key products, but the eurozone crisis is exacerbating the challenges facing AstraZeneca by causing austerity-ridden governments to cut the price they pay for drugs.

Products accounting for more than 40pc of sales at AstraZeneca will lose patent protection by the end of 2014. Its best-selling anti-psychotic drug, Seroquel, lost US patent protection in March, while the patent on Nexium for ulcers, the third-biggest seller, expires in America in 2014. The pair generated $10.3bn of sales last year.

AstraZeneca has sought deals to bolster its drug pipeline in the face of falling revenues. Earlier this month, the company said it would pay Bristol-Myers Squibb $3.4bn to co-develop the diabetes drugs of Amylin, which Bristol is acquiring for $5.3bn.

Simon Lowth, finance director and interim chief executive, said the process to find a replacement for former chief executive David Brennan is the “highest priority” of the chairman, Leif Johansson.